Is this a Normal Mod?

I have just bought a MK 3 , and its bone tight ,not one drop of oil in 35 hard miles...well up to 80 on the local b roads.
Anyway i have seen a very small bore pipe from the oil tank to a tee connecter on the carb balance pipe hose, it appears to be designed to vent the tank into the engine inlet manifolds....is that normal?

Haven't heard of it. No leaks; are you sure there is oil in it!!

Factory set-up for the MK III has the tank breather going to a separator,(I believe to plumb into factory airbox as mine didn't have the big box when I got it), then to the T in the manifold balance pipe.
I have the factory diagram in the workshop manual and can scan it if you need.

Yes, normal and by design set up to reduce crankcase emissions, also a good source for running on the lean side. I recommend that you remove this "system" and vent it into the airbox or into a small bore K&N.

RS

Braggart on a new to you C'do and no mess, dang it.
As much oil vapor as C'do's produce its a bad mod that just adds coking to chambers and lowers the octane rating. Vent to environment with check valve PCV in line with the crankcase breathing.

Mark IIIs shouldn't leak. The joint faces were substantially improved. Mine is dry too despite having covered more than 100,000 miles (and not just after a ride round the block either )They suffer eventually from the usual tacho seal weep and the gearbox camplate and quadrant 'O' rings will sweat after high mileage.

The breather system is a bit of a worry as overfilling the oil tank will dump it straight into the air filter and down the inlet tract, followed shortly afterwards by sticking inlet valves that then do their best to kiss the piston crowns.

john robert bould said:

Anyway i have seen a very small bore pipe from the oil tank to a tee connecter on the carb balance pipe hose, it appears to be designed to vent the tank into the engine inlet manifolds....is that normal?

Click to expand...

http://www.oldbritts.com/oillines.html

Thanks Lab,